The present invention relates to a quick-release fastening device and, more specifically to a so called "quick-change track lock" for securing of interior-design articles in an aircraft, helicopter or spacecraft or for securing load-restraining members on C-shaped retaining tracks laid in the floor or wall of the space/aircraft interior, comprising a main body; at least one detent member associated with the main body and serving to fix the track lock longitudinally in the retaining track; and a locking body guided in the main body and displaceable in the longitudinal direction of the track lock, said locking body comprising at least one mushroom-shaped locking member intended to engage the undercut portions of the retaining track.
Quick fastening devices are known and used in a variety of embodiments. They are in use in three different categories, namely for cooperation with retaining tracks of the categories (types) "light-duty track", "medium-duty track" and "heavy-duty track". A quick fastening device of this type is known from EP-A-0105675. If this track fastening device is used, the article that is to be secured can be secured on the retaining track directly in the position in which it was placed on the retaining track, it not being necessary to displace the article. The main body used in the known track fastening device comprises a channel with a T-shaped cross section, the locking body being guided in said channel. This publication, however, does not indicate the manner in which the locking body is displaced in the main body. Nor does it discuss how to establish a play-free, rattle-proof connection between the track fastening device and the retaining track.
Further quick fastening devices are known, for example, from German patent application 25 56 000, German patent specification 21 61 735 and U.S. Pat. No. 3,677,195. In each case, the mushroom-shaped locking members are rigidly connected to the respective main body, while the cylindrical detent pins provided as detent members are accepted, displaceable in their axial direction, in the respective main body. The corresponding actuating lever is used to raise or lower the detent pins in the main body. The track fastening device is installed in the retaining track in that the track lock is placed on the retaining track in a position in which the mushroom-shaped locking members are able, with their heads, to pass through the cutouts in the retaining tracks; subsequently, the track lock is displaced by half a pitch, i.e. by half the distance between two cutouts in the retaining track, in the longitudinal direction of the retaining track, with the result that the heads of the locking members come underneath the protrusions disposed between every two cutouts in the retaining tracks. Finally, by operation of the actuating lever, the detent pin is lowered and latches into a cutout in the retaining track, thereby preventing further longitudinal displacement of the track lock in the retaining track.
The quick fastening device as set forth in German patent specification 27 32 460 employs the same locking principle. In this case, however, the locking members are not rigidly mounted on the main body, but are disposed on plates that can be swiveled to a Might extent with respect to the main body, with the result that all the locking members are uniformly loaded. The same, aforedescribed locking principle is further employed by the track fastening device set forth in German patent application 36 31 097, wherein the detent pin is not guided in axially displaceable manner in the main body, but is disposed on a rocker arm swivelably held in the main body. Finally, the same, aforedescribed locking principle is employed by the fastening device as set forth in German patent application 38 04 354 and German patent specification 34 47 178, wherein the corresponding fastening devices, however, do not include an actuating 1ever. In these just-mentioned devices, a tool is used to displace the detent pin in its axial direction in the main body in order to cause the locking or release of the track fastening devices in the retaining track.
Finally, U.S. Pat. No. 4,185,799 discloses a track fastening device that comprises a number of individual components and is assembled in situ, i.e. on the retaining track. Consequently, this is not a quick-change track lock. The track fastening device is assembled/installed in such a manner that, first, a locking body with mushroom-shaped detent members is inserted from above into the retaining track--with the locking members passing through corresponding cutouts in the retaining track--and is then displaced by half a pitch in the longitudinal direction of the retaining track. Subsequently, a retainer is inserted into one of the cutouts in the retaining track and is pushed down onto the locking body, with the result that the locking body is locked against longitudinal displacement. Finally, the main body is pushed in the longitudinal direction of the retaining track onto a corresponding protrusion of the locking body and main body, locking body and retainer are clamped together by means of a bolt.
Therefore, common to all the aforementioned track fastening devices is the fact that the main body, carrying the aircraft interior-design article to be secured, is not in its final position when it is placed on the retaining track. Rather, in the aforementioned devices, the main body is first displaced on the retaining track in the longitudinal direction thereof in order to be brought into its final position. This has the disadvantage that the space available in aircraft interiors is not put to optimal use, since the articles to he secured cannot always be ideally positioned. This is because space is lost through the requirement that, in general, half a pitch, i.e. 0.5 inch by the prevailing standard, of space in the longitudinal direction of the retaining track be made available for the installation of the track lock. In many cases, the space required for displacement is not at all available, as a result of which the use of the known track fastening devices is rendered entirely impossible.